Synthesis of 2,3-Dihydro-1,4,5-benzodioxazocines. X-ray structure of 6-Phenyl-2,3-dihydro-1,4,5-benzodioxazocine

Abstract

Derivatives (6a-c) of the 1,4,5-benzodioxazocine ring system have been prepared in low-to-moderate yields by hydrazinolysis of {2-[2-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)oxyethyloxy]aryl}phenylmethanones(5a-c), and cyclization of the products at pH c. 4. Only in the case of (6b) was a trace of a cyclic dimer (7b) detected, in contrast to the analogous preparations of the 2H-1,5,6-benzodioxazonine derivatives (1a-c) where 18-membered cyclic dimers (8a-c) formed as by-products. The crystal and molecular structure of 6-phenyl-2,3-dihydro-1,4-5-benzodioxazocine (6a) has been determined by single-crystal X-ray methods.